Oxycodone is a semisynthetic derivative of morphine. It is orally active and is sometimes formulated with aspirin or acetaminophen. It is used to treat moderate to severe pain and has many properties in common with morphine. Its oral analgesic effect is approximately twice that of morphine. Oxycodone is metabolized via CYP450 2D6 and 3A4 enzyme systems. Excretion is via the kidney. Abuse of the sustained-release preparation (ingestion of crushed tablets) has been implicated in many deaths. It is important that the higher-dosage forms of the latter preparation be used only by patients who are tolerant to opioids.